was later proposed for I-75 itself; I-275 would have been the freeway to loop into downtown Detroit. The proposed length was increased by December 1955; the extended Michigan Turnpike would have run from a connection across the Ohio state line to Toledo north through Detroit and Saginaw and eventually to the southern end of the Mackinac Bridge. By the following April, any extensions were cancelled leaving the turnpike to its original termini; the east–west companion road was also cancelled at that time. The MTA proposed a state constitutional amendment in January 1956 that would allow the Michigan Legislature to issue state-guaranteed bonds for part of the MTA's construction expenses. According to The Wall Street Journal, the authority "struggled for survival" in the face of opposition from the MSHD just two months later; the department's actions impaired the authority's appropriations from the state legislature and its ability to sell the necessary bonds to pay for construction. When the federal government approved the Federal Aid Highway Act of 1956, Ziegler and the MSHD announced plans for a full freeway to run north through the Lower Peninsula and continue across to the Upper Peninsula. This announcement undermined the efforts to build the Michigan Turnpike. By August 1956, the MTA voted to reduce its operations to a skeleton staff, but moved forward in May 1957 on a bond sale to finance construction of the roadway. Financiers stated such a sale was only feasible if the turnpike was to be safe from competition. The Michigan Townships Association called for the abolition of the MTA in 1958. The legislature killed a bill to do so in June 1959, but it later voted to repeal the act that created the authority in 1962. Interstate Highway era The first sections of freeway for I-75 were opened in 1957, beginning with the southern section near the Ohio state line opened in October 1957. The Mackinac Bridge was opened to traffic on November 1, 1957; a new section of freeway and an interchange connected US 2 to the bridge on the northern end, and to US 27 and US 31 on the southern end. The MSHD formally proposed the I-75 number in 1958. On June 30 of that year, the first stretch of the "Fenton–Clio Expressway" opened. Construction on the Chrysler Freeway in Detroit started on January 30, 1959. The I-75 signs were first installed along the Detroit–Toledo Expressway in